England's "unimaginative" exam system is little changed from Victorian times and fails to prepare young people for modern working life, Eton's headmaster has said.

Tony Little said there was a risk that "misleading" test scores may become more important than education itself, and warned against a narrow focus on topping rankings.

"There is a great deal more to an effective and good education than jostling for position in a league table," Little wrote in a Viewpoint article for the Radio Times.

He said England's attempts to copy the highly academic schooling offered in areas of the far east such as Shanghai was ironic, since schools there were now looking at the value of giving children a more rounded education.

"Here is the irony; we seem intent on creating the same straitjacket the Chinese are trying to wriggle out of," he wrote. "We should be wary of emulating Shanghai just as they themselves see some value in the liberal values of an all-round education – something we have traditionally been good at."

Shanghai is rated the top education system in the OECD's Pisa tests (Programme for International Student Assessment), which compare the performance of children in 65 countries.

English children's comparatively poor performance in the rankings was cited by Michael Gove, the former education secretary, as justification for introducing more traditional exams, academies and free schools. Liz Truss, a former education minister, visited to Shanghai to learn the secrets of its success.

This year's school exam results are expected to vary wildly after a series of reforms including scrapping modular exams and shifting the balance between tests and coursework in favour of the former.

But Little said England's exam system was outdated. "[The exam system] obliges students to sit alone at their desks in preparation for a world in which, for much of the time, they will need to work collaboratively."

Little, who is due to retire next year, gave his support to a Lancashire primary school that found itself in the spotlight after a letter telling pupils them not to worry about their test results went viral.

Year 6 students at Barrowford primary in Nelson, Lancashire, were sent a signed letter from their headteacher, Rachel Tomlinson, and year 6 teacher Amy Birkett after receiving their SATs results. It said the school was proud of their efforts during the tests, but went on to say that the tests did not assess all of what made each of them "special and unique".